JP6614016B2 - AIR-COIL COIL, ITS MANUFACTURING METHOD, AND COIL COMPONENT USING AIR-CORE COIL - Google Patents

Description

  The present invention relates to an air core coil and a manufacturing method thereof, and more particularly to an air core coil using a wire having a thin wire diameter and a manufacturing method thereof. The present invention also relates to a coil component using such an air-core coil.

  In the air-core coil, the lead portion led out from the winding portion may spring back, and in this case, there is a problem that the lead portion is displaced from a desired position. As a method for solving such a problem, Patent Document 1 discloses a method of correcting the spring back by strongly bending the base of the lead portion.

JP-A-8-8136

  However, if the base of the lead part is strongly bent as in Patent Document 1, there is a risk that the insulating film covering the core material may be damaged, which may reduce the reliability of the coil component. In particular, when a wire having a small diameter is used, since the insulating film covering the core material is also thin, the insulating film may be easily damaged by bending.

  Therefore, the present invention provides an air-core coil that can stabilize the posture of the lead portion without reducing reliability even when a wire with a thin wire diameter is used, and a method for manufacturing the same, and An object of the present invention is to provide a coil component using such an air-core coil.

  An air-core coil according to the present invention includes a winding portion in which a wire is wound in an air-core shape, a first lead portion including one end of the wire led out from the winding portion, and a lead-out portion from the winding portion. An air-core coil including a second lead portion comprising the other end of the wire, wherein the first and second lead portions are formed by twisting a plurality of the wires. To do.

  According to the present invention, since the lead portion has a structure in which a plurality of wires are twisted, the weight increases in the lead portion. This makes it possible to stabilize the posture of the lead portion without strongly bending the base of the lead portion.

  In the present invention, the plurality of wires may be electrically separated or short-circuited. The former structure is obtained by twisting the lead portion and then cutting the tip portion. In this case, the length of the lead portion does not become longer than necessary.

  In this invention, it is preferable that the said wire is mutually fixed to the said winding part with the adhesive member. According to this, since the wire which comprises a winding part is integrated, even if it is a case where a wire diameter is thin, it becomes possible to stabilize the shape of a winding part.

  In this case, it is preferable that all of the plurality of wires constituting the first and second leads are bonded to the core portion by the adhesive member. According to this, it becomes possible to further stabilize the posture of the lead portion.

  A coil component according to the present invention includes a magnetic core including a magnetic material and a binder, the air core coil embedded in the magnetic core, and a first terminal electrode connected to the first lead portion of the air core coil. And a second terminal electrode connected to the second lead portion of the air-core coil.

  According to the present invention, it is possible to provide a surface mount type coil component suitable as a power supply coil.

  In the present invention, it is preferable that the first lead portion and the first terminal electrode, and the second lead portion and the second terminal electrode are all connected inside the magnetic core. In the coil component having such a structure, the lead portion is not led out of the magnetic core, so the lead portion cannot be held outside the magnetic core, and the stability of the lead portion is particularly important. is there.

  An air-core coil manufacturing method according to the present invention includes a winding part, a first lead part composed of one end of the wire led out from the winding part, and a winding part by winding the wire. A first step of forming a second lead portion composed of the other end of the derived wire and a conductor bundle composed of a plurality of the wires are formed by folding back the first and second leads. And a third step of twisting the conductor bundle.

  According to the present invention, it is possible to stabilize the posture of the lead portion by a simple method without strongly bending the root of the lead portion.

  In the present invention, it is preferable that the surface of the wire is covered with a fusion layer, and the fusion layer is melted by heating the winding portion after the first step. According to this, it is not necessary to separately supply an adhesive member to the winding part, and the process can be simplified.

  In this case, it is more preferable that the fusion layer is melted by heating the first and second lead portions after the third step. According to this, since the lead portion and the winding portion are bonded by the fusion layer, the posture of the lead portion can be further stabilized.

  In the present invention, after performing the third step, the ends of the first and second lead portions may be cut. According to this, it becomes possible to adjust the length of the lead portion to a desired length.

  As described above, according to the present invention, even when a wire having a thin wire diameter is used, an air-core coil capable of stabilizing the attitude of the lead portion without reducing reliability and a method for manufacturing the same. In addition, it is possible to provide a coil component using such an air-core coil.

FIG. 1 is a schematic perspective view showing an appearance of a coil component 10 according to a preferred embodiment of the present invention. FIG. 2 is a cross-sectional view of the coil component 10. FIG. 3 is a schematic perspective view for explaining the shape of the first terminal electrode 41. FIG. 4 is a schematic perspective view for explaining the internal structure of the coil component 10. FIG. 5 is a schematic external view for explaining the structure of the air-core coil 30. FIG. 5 is a schematic external view for explaining the structure of the air-core coil 31. FIG. 7 is a cross-sectional view of the wire W. FIG. 8 is a schematic diagram for explaining a method for manufacturing the air-core coil 30. FIG. 9 is a schematic diagram for explaining a method for manufacturing the air-core coil 30. FIG. 10 is a schematic diagram for explaining a method for manufacturing the air-core coil 30. FIG. 11 is a schematic diagram for explaining a method for manufacturing the air-core coil 30. FIG. 12 is a schematic diagram for explaining a method for manufacturing the air-core coil 30. FIG. 13 is a schematic diagram for explaining a method for manufacturing the air-core coil 30. FIG. 14 is a schematic external view for explaining the structure of the air-core coil 32 according to a modification.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a schematic perspective view showing an appearance of a coil component 10 according to a preferred embodiment of the present invention. FIG. 2 is a cross-sectional view of the coil component 10.

  As shown in FIGS. 1 and 2, the coil component 10 according to the present embodiment is provided on a magnetic core 20 having a substantially rectangular parallelepiped shape, an air core coil 30 embedded in the magnetic core 20, and a mounting surface 23 of the magnetic core 20. Two terminal electrodes 41 and 42 connected to the air-core coil 30 are provided. Although not particularly limited, the coil component 10 according to the present embodiment is a surface mount type coil component suitable as a power supply coil.

  The magnetic core 20 is made of a composite magnetic material including a magnetic material and a binder, and includes a lower magnetic core 21 and an upper magnetic core 22. As the magnetic material contained in the composite magnetic material, it is particularly preferable to use a soft magnetic metal powder having a high magnetic permeability. Specific examples include ferrites such as Ni—Zn, Mn—Zn, Ni—Cu—Zn, permalloy (Fe—Ni alloy), super permalloy (Fe—Ni—Mo alloy), sendust (Fe—Si—Al). Alloy), Fe—Si alloy, Fe—Co alloy, Fe—Cr alloy, Fe—Cr—Si alloy, Fe, amorphous (Fe-based), nanocrystal (nanocrystal), and the like. In addition, as the binder, thermosetting resin materials such as epoxy resin, phenol resin, silicone resin, diallyl phthalate resin, polyimide resin, and urethane resin can be used.

  The lower magnetic core 21 has a flat plate portion 21 a and a convex portion 21 b, and the air core coil 30 is placed on the flat plate portion 21 a so that the convex portion 21 b is inserted into the inner diameter portion of the air core coil 30. The upper magnetic core 22 is a portion in which the air-core coil 30 placed on the lower magnetic core 21 is embedded. Although not particularly limited, in the present embodiment, the convex portion 21b has a tapered shape, and thus, when the lower magnetic core 21 is formed using a mold, the convex portion 21b is formed from the mold. It is easy to come off.

  The air-core coil 30 is constituted by a coated conductor in which a core material such as copper is coated with an insulating coating. The air-core coil 30 includes a winding part 50 and first and second lead parts 51 and 52, the first lead part 51 is connected to the first terminal electrode 41, and the second lead part 52 is the first lead part 52. 2 terminal electrodes 42 (see FIG. 4). Although details will be described later, the lead portions 51 and 52 of the air-core coil 30 according to the present embodiment have a structure in which a plurality of wires W1 and W2 are twisted.

  As shown in FIG. 3, the first terminal electrode 41 has a mounting portion 43 located on the mounting surface 23 of the magnetic core 20 and a connecting portion 44 connected to the first lead portion 51. 44 penetrates the flat plate portion 21 a of the lower magnetic core 21. The second terminal electrode 42 has a similar structure. Then, as shown in FIG. 4, after the air core coil 30 is placed on the lower magnetic core 21, the lead portions 51 and 52 of the air core coil 30 are welded to the connection portions 44 of the terminal electrodes 41 and 42, and finally, If the air-core coil 30 is embedded by the upper magnetic core 22, the coil component 10 according to the present embodiment is completed. Although not particularly limited, in the present embodiment, the connection portions of the terminal electrodes 41 and 42 are provided at diagonal positions.

  FIG. 5 is a schematic external view for explaining the structure of the air-core coil 30.

  As shown in FIG. 5, the air-core coil 30 according to the present embodiment includes a winding portion 50 in which the wire W is wound in an air-core shape, and a first end composed of one end of the wire W led out from the winding portion 50. Lead portion 51 and a second lead portion 52 formed of the other end of the wire W led out from the winding portion 50. The wire W is a coated conductor in which a core material such as copper is coated with an insulating coating. The lead portions 51 and 52 are led out from the winding portion 50 in the radial direction, and are arranged at positions different from each other by 180 °. In the example shown in FIG. 5, the wire W has a single-wire structure, but a wire having a structure in which a plurality of covered conductors are integrated, such as a pair wire, may be used. In this case, the plurality of covered conductors may have a stranded wire structure.

  The wires W constituting the winding part 50 are fixed to each other by the adhesive member 60 and are thus self-held. The type of the adhesive member 60 is not particularly limited, but it is preferable to use a thermoplastic resin having a low melting point such as polyester. The bonding member 60 plays a role of temporary fixing for holding the wire W integrally in the step of embedding the air-core coil 30 in the magnetic core 20. Therefore, it is sufficient that the adhesive member 60 has a characteristic and an amount capable of self-holding the winding portion 50, and the adhesive force does not need to be excessively strong, and the usage amount may be minimized. Rather, if the amount of the adhesive member 60 used is too large, the proportion of the nonmagnetic material embedded in the magnetic core 20 increases, which is not preferable because the magnetic properties are degraded.

  The lead portions 51 and 52 have a configuration in which two wires W1 and W2 are twisted. More specifically, the wire W1 is an extended portion of the wire W constituting the winding part 50, and the wire W2 is separated from the wire W1, and the two wires W1 and W2 are twisted a plurality of times. It has a combined configuration. The wire W1 and the wire W2 are coated conductors having the same configuration, but in the example shown in FIG. 5, they are separate wires that are electrically separated from each other. However, like the air-core coil 31 according to another example shown in FIG. 6, the lead portions 51 and 52 may be formed by twisting one folded wire W1 a plurality of times.

  Thus, since the air-core coil 30 or 31 has a configuration in which two wires (wires W1 and W2 or two wires W1) are twisted, one untwisted wire The weight increases as compared to the case of wires. For this reason, even when a wire with a thin wire diameter is used, springback hardly occurs, and the position and posture of the lead portions 51 and 52 with respect to the wound portion 50 can be stabilized without strongly bending the root portion. Is possible. In addition, since the two wires are twisted together, they are not separated from each other. In addition, what is necessary is just to form the lead parts 51 and 52 by further twisting a pair of twisted wire, when using a twisted wire as the wire W which comprises the winding part 50 from the beginning.

  The lead parts 51 and 52 are fixed to each other by the adhesive member 60 as in the winding part 50. Further, as shown in FIGS. 5 and 6, it is preferable that an adhesive member 60 is also present between the root portions of the lead portions 51 and 52 and the winding portion 50. In this case, the lead portions 51 and 52 are provided. Can be more stable. In particular, not only the wire W1 that is an extension of the wire W constituting the winding part 50 is fixed to the winding part 50 by the adhesive member 60, but also the wire W2 is fixed to the winding part 50 by the adhesive member 60. Since the lead portions 51 and 52 are fixed to the winding portion 50 at two locations, the posture of the lead portions 51 and 52 can be further stabilized.

  Next, a method for manufacturing the air-core coil 30 will be described.

  First, the winding part 50 is formed by preparing the wire W and winding it. As shown in FIG. 7, the wire W is a three-layer covered conductor including a core material 71, a coating film 72, and a fusion layer 73. The core material 71 is made of a good conductor such as copper (Cu), and the surface thereof is covered with a coating film 72. The covering film 72 is made of an insulating material made of imide-modified polyurethane or the like, and its surface is covered with a thin fusion layer 73. The fusion layer 73 is a material of the adhesive member 60 and is made of an insulating resin material such as polyester. The melting point of the fusion layer 73 is preferably sufficiently lower than that of the coating film 72. As an example, the melting point of the imide-modified polyurethane is about 260 ° C., whereas the melting point of the polyester is about 70 ° C.

  Next, as shown in FIG. 8, the wire W is set on a winding jig having the rotary shaft 80 and the guide shafts 81 to 86, and the rotary shaft 80 is fixed with the wires W on the guide shafts 84 to 86 side fixed. Rotate. Thereby, the wire W is sent out from the guide shafts 81 to 83 side, and the wire W is wound around the rotation shaft 80. And if the rotation of the rotating shaft 80 is stopped at the timing of winding the required number of turns, the winding part 50 is formed around the rotating shaft 80. Here, the guide shafts 82 and 85 are used to form conductor bundles A and B composed of two wires W by folding back the wires W constituting the lead portions 51 and 52, respectively.

  Next, as shown in FIG. 9, the fusion layer 73 is melted by heating the winding part 50. The portion to be heated is shaded in FIG. The winding part 50 can be heated using an air heater or the like. Thereby, since the space between the wires W in the winding portion 50 is filled with the adhesive member 60, the wires W constituting the winding portion 50 are fixed to each other by the adhesive member 60 when cooled to room temperature.

  Next, as shown in FIG. 10, the remaining wires W are sandwiched outside the winding part 50 using the arms 87 and 88. The arm 87 sandwiches the conductor bundle A composed of the two wires W reciprocating between the guide shaft 81 and the guide shaft 82, and the arm 88 is reciprocated between the guide shaft 84 and the guide shaft 85. A conductor bundle B made of wires W is sandwiched.

  Next, as shown in FIG. 11, after retracting the guide shafts 82 and 85, the conductor bundles A and B are twisted by rotating the arms 87 and 88. Thereby, the two wires W are gradually twisted according to the rotation of the arms 87 and 88, and the lead portions 51 and 52 are gradually formed. Then, when the twisted portion has advanced to the vicinity of the guide shafts 81 and 84, the guide shafts 81 and 84 are retracted and further twisted as shown in FIG. At this time, by pulling the remaining wire W using the other arms 89 and 90, the twisted portion is gradually brought closer to the winding part 50.

  And as shown in FIG. 13, when the twist location reaches the winding part 50, the rotation of the arms 87 and 88 is stopped, and the twist location is heated with an air heater or the like, thereby forming the fusion layer 73. Melt. The portion to be heated is shaded in FIG. As a result, the two twisted wires W are fixed to each other by the adhesive member 60.

  Then, if the arms 87 and 88 are removed and unnecessary portions of the wire W are cut, the air-core coil 30 or 31 shown in FIG. 5 or 6 is completed. At this time, if only the portion pulled by the arms 89 and 90 is cut, the structure of the air-core coil 31 shown in FIG. 6 can be obtained. Further, if the portion sandwiched by the arms 87 and 88 is also cut, the structure shown in FIG. The structure of the air-core coil 30 shown in FIG.

  Since the lead portions 51 and 52 of the air-core coil 30 or 31 thus created have a configuration in which two wires W are twisted, the position and posture thereof are stable as described above. To do. In particular, when the roots of the two wires W1 and W2 are both fixed to the winding part 50 by the adhesive member 60, the positions and postures of the lead parts 51 and 52 can be further stabilized. Thereby, for example, the lead portions 51 and 52 are not opened by the spring back and separated from the winding portion 50.

  When the coil component 10 is created using such an air core coil 30, the air core coil 30 is placed on the lower magnetic core 21 as shown in FIG. The lead parts 51 and 52 of the air-core coil 30 are welded. At this time, in the conventional air-core coil, the posture of the lead portions 51 and 52 is not stable, and there are cases where welding to the terminal electrodes 41 and 42 is difficult. In this embodiment, the lead portions 51 and 52 Since the posture is stable, welding to the terminal electrodes 41 and 42 can be easily performed. Thereafter, when the air core coil 30 is embedded by the upper magnetic core 22, the coil component 10 according to the present embodiment is completed.

  Here, if the coil part is a type that embeds the air core coil with the lead part led out to the outside of the magnetic core, the lead part led out of the magnetic core can be held by some jig, so the lead part Even if the posture is not particularly stable, there will be no major trouble in the work. However, such a jig cannot be used in a product in which the lead parts 51 and 52 and the terminal electrodes 41 and 42 are connected inside the magnetic core 20 as in the coil component 10 according to the present embodiment. In order to improve workability, it is very important that the postures of the lead portions 51 and 52 are stable. And in this embodiment, since it has the structure by which the lead parts 51 and 52 were twisted, the attitude | position of the lead parts 51 and 52 is stabilized, and the lead parts 51 and 52 and the terminal electrodes 41 and 42 are connected. It is possible to manufacture the coil component 10 of the type that is connected inside the magnetic core 20 with good workability.

  In addition, in this embodiment, since the lead portions 51 and 52 are both formed of two wires, it is possible to increase the welding strength for the terminal electrodes 41 and 42 as compared with the conventional case.

  FIG. 14 is a schematic external view for explaining the structure of the air-core coil 32 according to a modification.

  The air-core coil 32 shown in FIG. 14 is different from the air-core coil 30 shown in FIG. 5 in that two wires W and W10 are wound concentrically. These two wires W and W10 both constitute a winding part 50 wound in an air-core shape, and one wire W is the first and second leads led out from the winding part 50. The other wire W <b> 10 includes third and fourth lead portions 53 and 54 led out from the winding portion 50.

  The wires W and W10 constituting the winding part 50 are fixed to each other by the adhesive member 60 and are self-held. The third and fourth lead portions 53 and 54 also have a configuration in which two wires W11 and W12 are twisted, respectively, and the root portions of the wires W11 and W12 and the winding portion 50 are provided. It is fixed by an adhesive member 60. Thereby, it becomes possible to stabilize the attitude | position of the lead parts 51-54. In the example shown in FIG. 14, the four lead portions 51 to 54 are led out from the winding portion 50 at an angle of 90 ° to each other, but the present invention is not limited to this.

  The air-core coil 32 having such a configuration can be used for a coil component having a four-terminal configuration.

  Thus, the air-core coil in the present invention may be one in which a plurality of wires are wound concentrically. In this case, the number of wires is not limited to two and may be three or more.

  The preferred embodiments of the present invention have been described above, but the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention. Needless to say, it is included in the range.

  For example, in the above embodiment, two wires W constituting the winding part 50 are bundled to form conductor bundles A and B, and these are twisted. However, three wires W constituting the winding part 50 are twisted. The lead portions 51 and 52 may be formed by twisting the bundle of conductors bundled as described above.

DESCRIPTION OF SYMBOLS 10 Coil components 20 Magnetic core 21 Lower magnetic core 21a Flat plate part 21b Convex part 22 Upper magnetic core 23 Mounting surface 30-32 Air-core coil 41, 42 Terminal electrode 43 Mounting part 44 Connection part 50 Winding part 51-54 Lead part 60 Adhesive member 71 Core material 72 Coating film 73 Fusion layer 80 Rotating shaft 81-86 Guide shaft 87-90 Arm A, B Conductor bundle W, W1, W2, W10-W12 Wire

Claims (8)

From a winding part in which a wire is wound in an air-core shape, a first lead part composed of one end of the wire led out from the winding part, and from the other end of the wire led out from the winding part An air-core coil including a second lead portion,
The first and second lead portions are formed by twisting a plurality of the wires,
The air-core coil , wherein the plurality of wires are electrically separated . The air-core coil according to claim 1 , wherein the wire is fixed to each other by an adhesive member in the winding portion.   3. The air-core coil according to claim 2, wherein each of the plurality of wires constituting the first and second leads is bonded to the core part by the adhesive member. 4. A magnetic core including a magnetic material and a binder, an air core coil according to any one of claims 1 to 3 embedded in the magnetic core, and a first core connected to the first lead portion of the air core coil. A coil component comprising: one terminal electrode; and a second terminal electrode connected to the second lead portion of the air-core coil. Said first lead portion and the first terminal electrode, and, wherein the second lead portion and the second terminal electrode, according to claim, characterized in that both are connected by inside the magnetic core 4 Coil parts as described in. By winding a wire, a winding portion, a first lead portion made of one end of the wire led out from the winding portion, and a second lead made from the other end of the wire led out from the winding portion. A first step of forming two lead portions;
A second step of forming a conductor bundle composed of a plurality of the wires by folding the first and second leads, respectively;
A third step of twisting the conductor bundle ,
After the third step is performed, the tips of the first and second lead portions are cut . The surface of the wire is coated with a fusion layer,
The method of manufacturing an air-core coil according to claim 6 , wherein after the first step is performed, the fused layer is melted by heating the winding part. 8. The method of manufacturing an air-core coil according to claim 7 , wherein after the third step is performed, the fusion layer is melted by heating the first and second lead portions.

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